Revert of Revert of Clean up Smart Lock cryptohome keys logic:

chrome/browser/signin/easy_unlock_service.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_SIGNIN_EASY_UNLOCK_SERVICE_H_
 #define CHROME_BROWSER_SIGNIN_EASY_UNLOCK_SERVICE_H_
 
 #include <set>
 #include <string>
 
@@ skipping 65 matching lines @@
   virtual std::string GetUserEmail() const = 0;
 
   // Launches Easy Unlock Setup app.
   virtual void LaunchSetup() = 0;
 
   // Gets/Sets/Clears the permit access for the local device.
   virtual const base::DictionaryValue* GetPermitAccess() const = 0;
   virtual void SetPermitAccess(const base::DictionaryValue& permit) = 0;
   virtual void ClearPermitAccess() = 0;
 
-  // Gets/Sets/Clears the remote devices list.
+  // Gets/Sets the remote devices list.
   virtual const base::ListValue* GetRemoteDevices() const = 0;
   virtual void SetRemoteDevices(const base::ListValue& devices) = 0;
-  virtual void ClearRemoteDevices() = 0;
 
   // Runs the flow for turning Easy unlock off.
   virtual void RunTurnOffFlow() = 0;
 
   // Resets the turn off flow if one is in progress.
   virtual void ResetTurnOffFlow() = 0;
 
   // Returns the current turn off flow status.
   virtual TurnOffFlowStatus GetTurnOffFlowStatus() const = 0;
 
@@ skipping 180 matching lines @@
   bool tpm_key_checked_;
 
   ObserverList<EasyUnlockServiceObserver> observers_;
 
   base::WeakPtrFactory<EasyUnlockService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EasyUnlockService);
 };
 
 #endif  // CHROME_BROWSER_SIGNIN_EASY_UNLOCK_SERVICE_H_